Reusing software: issues and research directions

Software productivity has been steadily increasing over the past 30 years, but not enough to close the gap between the demands placed on the software industry and what the state of the practice can deliver; nothing short of an order of magnitude increase in productivity will extricate the software industry from its perennial crisis. Several decades of intensive research in software engineering and artificial intelligence left few alternatives but software reuse as the (only) realistic approach to bring about the gains of productivity and quality that the software industry needs. In this paper, we discuss the implications of reuse on the production, with an emphasis on the technical challenges. Software reuse involves building software that is reusable by design and building with reusable software. Software reuse includes reusing both the products of previous software projects and the processes deployed to produce them, leading to a wide spectrum of reuse approaches, from the building blocks (reusing products) approach, on one hand, to the generative or reusable processor (reusing processes), on the other. We discuss the implication of such approaches on the organization, control, and method of software development and discuss proposed models for their economic analysis. Software reuse benefits from methodologies and tools to: (1) build more readily reusable software and (2) locate, evaluate, and tailor reusable software, the last being critical for the building blocks approach. Both sets of issues are discussed in this paper, with a focus on application generators and OO development for the first and a thorough discussion of retrieval techniques for software components, component composition (or bottom-up design), and transformational systems for the second. We conclude by highlighting areas that, in our opinion, are worthy of further investigation     

Dopant Engineering for Spiro-OMeTAD Hole-Transporting Materials towards Efficient Perovskite Solar Cells

One of the most prominent hole-transporting material (HTM) for hybrid perovskite solar cells has been 2,2″,7,7″-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (spiro-OMeTAD), which is commonly doped with metal bis(trifluoromethylsulfonyl)imide (M(TFSI)_n) salts that contribute to generating the active radical cation HTM species. The underlying role of the metal cation, however, remains elusive. Here, the effect of metal cations (M = Li, Zn, Ca, Cu, and Sc) on doping spiro-OMeTAD is analyzed by a combination of techniques, including electron paramagnetic resonance spectroscopy and cyclic voltammetry, which is complemented by photovoltaic device and hole mobility analysis. As a result, the authors reveal the superiority of Zn(TFSI)₂ salts in device performances as compared to the others, including redox-active Cu(TFSI)₂. This analysis thereby unravels new design principles for dopant engineering in HTMs for hybrid perovskite photovoltaics.     

Makespan minimisation with sequence-dependent machine deterioration and maintenance events

This paper addresses the minimal makespan parallel machine problem where machines are subject to preventive maintenance events of a known deterministic duration. The processing time of a job depends on its predecessors since the machine’s last maintenance. The paper proposes some dominance criteria for sequences of jobs assigned to a machine, and uses these criteria to design constructive heuristics to this NP-hard problem. The computational investigation determines the parameters that make a hard instance and studies the sensitivity of the heuristics to these parameters.     

Epidemiology of end‐stage renal disease and hemodialysis treatment in Serbia at the turn of the millennium

The study presents the epidemiological features of patients treated with renal replacement therapy (RRT) in Serbia from 1997 to 2009 and compares the results of hemodialysis treatment in 1999 and 2009. Epidemiological data were obtained from the National Registry of RRT patients and data on hemodialysis treatment from special surveys conducted in 1999 and 2009. Within the period 1997–2009 the incidence of patients on RRT increased from 108 to 179 per million population (pmp), prevalence rose from 435 to 699 pmp, while mortality rate fell from 20.7% to 16.7%. The frequency of patients with glomerulonephritis decreased, while that of patients with diabetes and hypertensive nephropathy increased. In late 2009 there were 5208 patients receiving RRT in Serbia. Within the examined period new hemodialysis and reverse osmosis equipment were purchased, high‐flux dialyzers with synthetic membranes were increasingly used and the number of patients receiving hemodiafiltration increased to 17.6%. Kt/V greater than 1.2 was recorded in 16% of the patients in 1999 but 52% in 2009. Options for correction of anemia and mineral disorders have also improved. The percentage of patients with HbsAg (13.8% vs. 4.8%) as well as anti‐hepatitis C virus antibodies positive patients (23.2% vs. 12.7%) was significantly lower in 2009 than in 1999. Both the incidence and prevalence of RRT patients in Serbia are rising continuously, while the mortality rate is falling. More favorable conditions for dialysis treatment have brought about significant improvement in the results over the last 10 years.     

Microscopic analysis of recycled paper effect on print quality parameters

To determine whether the geometrical accuracy of small printed elements does not worsen on recycled paper, microscopic analysis of the dot area and the graphic elements raggedness printed on different types of recycled and coated papers at different screen ruling was carried out. Experimental tests have shown that geometrical accuracy of small elements printed on recycled paper/cardboard, in comparison to pictures printed on primary production paper is almost the same. Microsc. Res. Tech. 76:890–892, 2013. © 2013 Wiley Periodicals, Inc.     

The influence of ECAP on the small punch creep of Al–4 vol.% Al<Subscript>4</Subscript>C<Subscript>3</Subscript> composite

The creep behaviour of a composite based on an aluminium matrix reinforced by 4 vol.% Al₄C₃ was studied at temperatures of 623 and 723 K by small punch testing with a constant force. The composite was tested in two different states: (i) as received by mechanical alloying with hot extrusion (HE) as the final operation and (ii) with equal channel angular pressing (ECAP) superimposed on the hot-extruded material. The ECAP does not improve the observed creep resistance. The reduction of force leading to the same deflection rate is not very significant. This points out that the ECAP process of the present composite, which produces substantial strengthening at lower temperatures, is not accompanied by pronounced weakening of creep resistance at elevated temperatures. The threshold force in the ECAP material is about 5 N weaker than in the HE material.     

Influence of inorganic anions on electrochemical behaviour of pyrite

This work gives an investigation of pyrite behaviour during anodic oxidation in solutions of four inorganic acids: sulphuric, hydrochloric, phosphoric and perichloric acid. In wider range of concentrations, the influence of acids on following parameters was investigated: rate of establishment and corrosion potential value, Tafel's slope, corrosion current and electrodic reaction order. Based on potentiodynamic and chronoamperometric investigations, it was found out that pyrite oxidation is developed in three regions conditionally named active, passive and transpassive region. It was also found out that pyrite is intensively dissolved at potentials higher than 0.75 V versus SCE and that oxidation rate of pyrite is the highest in hydrochloric acid solutions (≥1 M HCl). By comparison of obtained results, it was concluded that there are no distinctive differences in pyrite behaviour during anodic oxidation in solutions of investigated acids.     

A QCA design and energy analysis of binary semaphore with a comprehensive case study

Innovations in Systems and Software Engineering - Quantum dot cellular automata appeared as a comprehensive solution to the shortfalls CMOS technology is facing in case of nanoscale...